Rotor of an ultrasonic test device for detection of oblique deflects

ABSTRACT

A rotor of on ultrasonic testing device for rotation-symmetrical test-pieces has drillings arranged in pairs for test head supports and test head supports arranged in these drillings. These supports are longitudinally adjustable along the axis of the drilling. The supports are sealed in the drilling and carry at least one test head. The drillings arranged in pairs are arranged in staggered array along the axis of rotation of the rotor or around the periphery of the rotor. Each pair has a rotary drive which as a shared activating system and facilitates synchronous rotation in an opposite direction of the two test head supports of the pair around the axis of the drilling.

The invention pertains to a rotor of an ultrasonic test device forrotationally symmetrical test pieces, especially tubes and bars. Therotor has at least one bore for a test probe mount. The bore holds atest probe mount, which a) can be longitudinally adjusted in thedirection of the axis of the bore, b) is sealed in the bore by a gasket,and c) holds at least one test probe. In this rotor, which isanticipated in DE-U-901 0066, the test probe mounts can be angularlyadjusted, thereby making it possible to detect oblique defects lyingwithin a given angular range.

In practical situations, it was then found that oblique defectsfrequently occur in such a way that they are present in a positiveangular range, measured relative to the axis of the test piece, and in anumerically equal, but negative angular range. The detection of thesekinds of oblique defects with the previously known rotor is difficult.

The goal of the invention was to further develop the previously knownrotor of the type described at the beginning in such a way that it wouldbe possible to determine not only the types of defects that can alreadybe detected with existing equipment, but also to simplify the detectionof oblique defects that occur both in a positive angular range (measuredrelative to the axis of the test piece) and in a numerically equal, butnegative angular range.

The oblique defects can be systematically detected in a positive angularrange (relative to the axis of the test piece) by the first test probemount of the pair, and the oblique defects in the numerically equal, butnegative angular range can be detected by the second test probe mount.By adjusting the interplay of the two test probe mounts from theoutside, it is possible to detect oblique defects of a desiredorientation. In this connection, the equipment of the invention can bequickly adapted to the specific test objective.

The goal of the invention was to further develop the previously knownrotor of the type described at the beginning in such a way that it wouldbe possible to determine not only the types of defects that can alreadybe detected with existing equipment, but also to perform oblique errortesting in ultrasonic rotational test systems.

In accordance with the invention, starting with the rotor of the typedescribed at the beginning, this goal is achieved by providing pairs ofbores, which are arranged in staggered fashion in the direction of theaxis of rotation of the rotor, and that a rotational drive is assignedto each test probe mount of a pair, which rotational drive has a commoncontrol and allows synchronous, opposing rotation of the two test probemounts of the pair about the given axis of the bore.

In accordance with the invention, it is possible systematically todetermine oblique defects that lie within a given angular range. In thisconnection, a minimum of one test probe of the first test probe mount ofa pair is set to determine oblique defects of a first angular range,while a minimum of one test probe of the second test probe mount of thepair detects oblique defects of another angular position. Especiallyadvantageous in this regard is a design in which the oblique defect isdetected by the first test probe mount of the pair in a positive angularrange (relative to the axis of the test piece), and the oblique defectis detected by the second test probe mount in the negative angular rangeof the same magnitude. By adjusting the interplay of the two test probemounts from the outside, it is possible to detect oblique defects of adesired orientation. In this connection, the equipment of the inventioncan be quickly adapted to the specific test objective.

Oblique defects arise, for example, in the production of tubes or barsby the continuous casting or continuous drawing process, if theproduction process also involves rotation (torsion). The generally arealdefects may also by variably inclined to their given angular positionrelative to the axis of the test piece. To assure reliable detection, itis proposed, in a further modification, that each test probe mount havetwo identically designed test probes, whose central test beams lie in aplane, which preferably runs through the central axis of the two boresof the pair of test probe mounts.

In this connection, it is especially advantageous if the central testbeams of the test probes of a pair intersect at a point located a fewcentimeters from the test probes. In the practical performance of thetest, this point of intersection is adjusted in such a way that it lieson or near the vertical line of a test piece. In this way, when the twotest probe mounts of a pair are rotated, the geometry undergoespractically no change during the ultrasonic irradiation, which is agreat advantage.

Furthermore, it was found to be advantageous to arrange a given pair oftest probe mounts in a cylindrical test probe holder, which has the twobores for the test probe mounts and in turn is mounted in a mountingbore of the rotor, holds the rotational drive, including the control,and is sealed in the mounting bore in such a way that it can be moved inthe longitudinal direction. In this way, the two test probe holders of apair can be adjusted together in the longitudinal direction of thebores; this also simplifies the design and operation of the equipment.

It is also possible to have more than two, preferably identicallydesigned, test probes per test probe mount. An even number of testprobes is advantageous. They are preferably uniformly distributed on acircular arc.

Other advantages and features of the invention are specified in thesecondary claims and in the following description of a specificembodiment of the invention, which is explained with reference to thedrawings. It is understood that the invention is by no means limited tothis specific example.

FIG. 1 shows an axial section (schematic) through a rotor with a pair oftest probe mounts, each of which has two test probes.

FIG. 2 is a view along line II--II in FIG. 1.

FIG. 3 is a cross section in the region of line III--III in FIG. 1.

FIG. 4 is a schematic representation for illustrating the processsequence. The drawing shows a cylindrical test piece, above which thereare two test probe mounts, each of which has two test probes displacedfrom each other by 180 degrees.

FIG. 5 is a perspective front view of a system as shown in FIG. 4, butthe drawing shows only two test probes of a test probe mount, which isotherwise not shown in detail.

This specific embodiment, especially FIG. 1, shows a section of a rotor20, which can be rotated around a test piece 22, which passes throughits main bore 21. The axis 24 of this test piece coincides with the axisof rotation of the rotor 20. A radial mounting bore 26 is formed in therotor 20. It passes through the rotor and thus extends from the outersurface of the rotor to its inner surface. A mount 28 is inserted in thebore. It can be moved in the direction of the axis of the mounting bore26 by means of an adjusting device (not shown, since it is state of theart).

The mount 28 has two bores 30 positioned an equal distance from the axisof the mounting bore 26 and parallel to it. The centers of the two bores30 are displaced in the direction of the axis 24 of the test piece andlie as close as possible to each other. The center axis of these twobores 30 coincides with the axis of the mounting bore 26. Each bore 30contains a test probe mount 32; the two test probe mounts 32 form a pairand are identical in design. Each test probe mount 32 has two testprobes 34, which are also identical in design. They are arranged on acircular arc around the axis of the bore 30, displaced from each otherby 180° and directed towards the test piece 22. They are mountedobliquely in the test probe mount 32, with the result that their centraltest beams 35 intersect at intersection point 36. In other words, thecentral test beams 35 of the two test probes 34 of a test probe mount 32form a V-shaped configuration. The point of intersection 36 is locatedon the top 38 of the cylindrical test piece 22, regardless of therotational orientation of the two test probes 34 of each test probemount 32.

The two test probe mounts 32 of a pair are rotationally connected. Thisis accomplished by means of a rotational drive 40, which acts on bothtest probe mounts 32 and has a control 42, which is accessible on theouter cylindrical surface of the rotor 20 and is designed, for example,as a polyhedron.

The rotational drive 40 can be designed in any desired way, as long asit satisfies the requirement that both test probe mounts 32 arerotationally connected with each other in such a way that the rotationof one test probe mount 32 through a certain angle causes rotation ofthe other test probe mount of the pair through the same angle. However,the two test probe mounts of a pair rotate in opposite directions.

In the concrete example shown here, a radially toothed gear 44, 46 isprovided on the radially outer end of each test probe mount 32. Itsdiameter corresponds to the diameter of the bore 30. The two gears 44,46 are engaged with each other and are angularly displaced relative toeach other by half a tooth space. They produce rotational connection ofthe two test probes 34 of the pair. The gear 46 of the test probe mount32 on the right in FIG. 1 has a greater axial length and at the sametime is used for the drive. For this purpose, a drive gear 48, which isalso radially toothed, engages the upper area of the gear 46; the drivegear 48 is connected with the control 42 of the rotational drive 40 viaa reduction gear, which is not shown in detail here. A scale is alsoprovided here, on which the present rotational position of the testprobes 34 or the test probe mounts 32 can be read. These things are partof the present state of the art and therefore are not shown in detail.

FIG. 2 shows a view radially outward towards the two test probe mounts32 and the rotor 20. The connecting line 50, 52 of the two test probes34 of the two test probe mounts 32 runs at an angle of ca. 90° to theaxis of rotation of the rotor 20. During practical operation, the twotest probe mounts 32 are adjusted in such a way that the angularposition has the same absolute value and differs only in sign. This hasthe effect that one of the test probe mounts detects oblique defects inthe positive angular position, while the other test probe mount detectscorresponding defects in the negative angular position.

FIG. 3 shows the rotational drive 40. The two gears 44, 46 areessentially the same in design, except for their different radialdimensions. The drive gear 48 is engaged with the right gear 46 and inturn is rotationally connected with a rod that is part of the control42.

If the two test probes 34 of each test probe mount 32 are aligned insuch a way that their connecting line 50, 52 runs perpendicularly to theaxis 24 of the test piece, longitudinal defects can be detected. Thiscorresponds to the representation shown in FIG. 1. On the other hand, ifthe two test probes 34 of each test probe mount 32 are aligned in such away that their connecting line 50, 52 runs parallel to the axis 24 ofthe test piece, transverse defects can be detected. In the intermediateangular range above 0° and below 90°, in which the two test probe mounts32 can be fixed in any desired position, oblique defects of thecorresponding orientation are detected.

When a 180° rotation of the two test probe mounts 32 is performed, thesame state is obtained as before from a measuring technology standpoint.

The measuring process will now be explained with reference to theschematic drawings in FIGS. 4 and 5. FIG. 4 shows a top view, and FIG. 5shows a corresponding front perspective view. Above the cylindrical testpiece 22, there are two (or only one in FIG. 5) test probe mounts 32,which are only indicated by their respective test probes 34 and theircircle of movement 54. The test probes 34 of each test probe mount arealigned in such a way that their central test beams 35 run together in aV-shaped configuration to a point of intersection 36, which in therepresentation shown here is located perpendicularly below the center ofthe circle of movement 54 of the two test probes 34. This point ofintersection lies on the top 38 of the cylindrical test piece 22.Directly below it there is an oblique defect 56. For the left pair oftest probes 34, it runs at an angle of plus 15° to the axis 24 of thetest piece, and for the two test probes 34 of the other test probe mount32 of the pair (on the right in FIG. 4), it runs at an angle of minus15° to the axis 24 of the test piece. The connecting line 50 or 52 ofthe two test probes 34 runs at right angles to it. In this way, thecentral test beams 35 hit the oblique defect 56 transversely to itslongitudinal dimension. Since the test probes 34 apply the ultrasonicradiation obliquely, they can preferentially detect oblique defects 56that are inclined in the radial direction. In this way, each of the twotest probes 34 of a test probe mount preferentially detects a differentinclination orientation of oblique defects 56.

We claim:
 1. A rotor of an ultrasonic test device for rotationallysymmetrical test pieces wherein:the rotor has a cylindrical outersurface and is formed with a main bore having an axis of rotation, amounting fixture coupled to the rotor, the mounting fixture being formedwith at least one pair of closely neighboring test probe mount bores,wherein the test probe mount bores are staggered relative to each otherwith respect to the axis of rotation, each of the test probe mount boreshaving a test probe mount axis lying in a plane perpendicular to theaxis of rotation, at least one pair of test probe mounts, the pair oftest probe mounts having a first and second test probe mount, each testprobe mount being engaged in one of the pair of test probe mount bores,each test probe mount being sealed in the test probe mount bore by agasket and being longitudinally adjustable along the test probe mountaxis, a least one test probe engaged in each said test probe mount, arotational drive coupled to the at least one pair of test probe mounts,the rotational drive having a common control that is accessible on theouter cylindrical surface of the rotor, the rotational drive providingsynchronous, opposing rotation of the pair of test probe mounts in thetest probe mount bore, each test probe mount rotating about the testprobe mount axis, whereby oblique defects in a positive angular rangerelative to the axis of rotation can be detected by the first test probemount of the pair, and oblique defects in a numerically equal negativeangular range can be detected by the second test probe mount of thepair.
 2. The rotor of claim 1, wherein each test probe mount of the pairholds two identically designed test probes, each test probe having acentral test beam, the central test beams of the two test probes lyingin a plane, which runs through the test probe mount axis.
 3. The rotorof claim 1, further comprising:a mounting bore formed in the rotor, themounting bore having a mounting bore axis perpendicular to the axis ofrotation, the mounting bore extending from the cylindrical outer surfaceto the main bore of the rotor,said mounting fixture being cylindrical inshape and engaged in the mounting bore, the mounting fixture beingformed with the at least one pair of test probe mount bores andcontaining the rotational drive and the common control, the mountingfixture being engaged in the mounting bore such that it can be moved inthe longitudinal direction along the mounting bore axis.
 4. The rotor ofclaim 2, wherein the test piece has a surface and the central test beamsof the test probes intersect in a point of intersection, which islocated on the surface of the test piece.
 5. The rotor of claim 1,wherein an even number of test probes are uniformly circularlydistributed in each test probe mount.
 6. The rotor of claim 1, whereinat least two pairs of test probe mounts are arranged at an equal spacingangle.
 7. The rotor of claim 2, wherein the test piece has an axis whichis coincident to the axis of rotation and the central test beams runperpendicularly to the test piece axis in a selected rotational positionof the two test probe mounts of the pair.
 8. The rotor of claim 1,wherein each of the test probes of the pair of test probes, when set atan identical absolute angle, are located at an identical distance from atest piece.
 9. The rotor of claim 1, wherein each of the test probes ofa test probe mount are oriented at an angle of 10° to 25°, relative tothe test probe mount axis.
 10. The rotor of claim 1, wherein the testprobes are connected to each other by a device for adjusting an angle ofinclination of the test probes, transverse to the test probe mount axisand the axis of rotation, such that it possible to adjust the testprobes at an angle greater than 0° and less than 45°.
 11. The rotor ofclaim 5, wherein four test probes are uniformly circularly distributedin each test probe mount.
 12. The rotor of claim 10, wherein each of thetest probes of the pair are oriented at an angle of 17°, relative to thetest probe mount axis.